Die construction for forming corrugated sheets



Aug. 9, 1960 T. o. WELINDT 3 3 DIE CONSTRUCTION FOR FORMING CORRUGATED SHEETS Filed !lay 6, 1957 3 Sheets-sheet 1 FIG.

INVENT Theodore awel'n t BYJW M ATTORNEYS.

1950 T. o. WELINDT 2,948,325

DIE CONSTRUCTION FOR FORMING CORRUGATED SHEETS Filed May 6, 1957 3 Sheet s-Sheet 2 .FIG.2.

x INVENTIOR. 'Theodore awelndt h-M #Ja AT TO R NEYS.

' templated of carrying out the invention r' 2948325 Ufllted p t t g i Patented Au e, 1960 DIE CONSTRUCTION FOR FORMING CORRUGATED SHEETS Theodo'e 0. Welindt, Kankakee, 111., assiguor to A. 0. Smith Corporation, Milwaukee, Wis., a corporation of New York p Filed May 6, 1957, Ser. No. 657,3o6

Claims. (Cl. 53-76 This-invention relates to an apparatus for forming corrugated sheet metal and more particularly to an apparatus capable of producing relatively deep corrugations.

In the past, numerous devices have been used for producing shallow corrugations. In these devices, corrugations are formed in succession by a forming member which bends and shapes the metal while one or more holding members clamp the previously formed corrugations securely in place, thereby preventing any slipping of the metal during the forming process.

Devices capableofproducing relatively deep corru- .gations, generally operate to form the metal in stages, bending one side of the corrugation and then the other by means of movable formng members which work in p pairs to form the metal therebetween. In this type of apparatus, the metal is not distorted nor stretched and, thus, the forces tending to cause slipping of the metal during the forming process are, for all practical pur- V poses, negligible.

This invention is directed to a new and useful improvement in a die construction for'forming deeply'corrugated metal sheets and includes a lower die having a corrugated working surface and a cooperating upper die. The upper die is comprised of a plurality of die members each of which cooperates with the corrugated working surface of the lower die `to act upon the metal sheet disposed therebetween as the two dies are moved toward one another. In particular, the upper die 'is comprised of a forming member which successively forms the corrugations in the metal sheet, a pair of spring-biased holding members disposed adjacent to the forming member and which clamp a portion of the previously formed metal sheet to prevent movement thereof during the forming process, and a plurality of sizing members disposed adjacent to the holding members and which act upon a portion of the previously formed corrugations during the forming process to insure uniformity and accura'cy of the corrugations. As successive corrugations are formed, 'the dies are separated or opened to allow the metal sheet to be advanced further into the appar'atus, thus enabling any length of metal to be corrugated in a continuous process.

Accordingly, it may be stated that an object of this apparatus is the successive formation of relatively deep 'corrugations in a metal sheet in a continuous process.

Another object of this apparatus is the sizing and shaping of 'previously formed corrugations to insure uniformity and accuracy in the final corrugations.

A further object of this apparatus is" the formation of corrugations by means of a relativelysimple and rugged machine containing few movng parts;

Further objects of the apparatus will appear in the course of the following description.

The drawings illustrate the best mode presently con- !In the drawings: A i

' Figure 1 is a longitudinal section of the apparatus show- 2 ing the cooperating dies in the open position With the metal sheet disposed therebetween;

Fig. 2 shows the cooperating dies as the forming member contacts the metal sheet at the start of forming a corrugation therein;

Fig. 3 is a view similar to Figure 1 showing the dies in the closed position;

Fig. 4 is a transverse section of the apparatus taken on line 4-4'of Fi'g. 3.

Fig. 5 is a transverse section taken on line 5-5 of Fig. 3; and i V i Fig. 6 is a perspective view of the completed corrugated metal sheet.

Referring to the drawings and in particular to Figure 1, the apparatus comprises a stationary lower die 1 which is attached to a base plate 2. The working surface of the lower die'is formed of a series of corrugations 3 having a contour conforming to that desred in the corrugations 4 in the metal sheet 5. As best seen in Fig. 6, the corru- -gations 4 have a depth substantially equal to or slightly less than the pitch.

An upper die 6, which is attached to platen 7, is disposed to cooperate with the lower die 1 and platen 7 is mounted for vertical movement by suitable means, not shown. The upper die 6 includes an integral forming member 8 disposed to cooperate with the corrugated working surface of the lower die 1 to form the metal sheet 5 therebetween. As the platen 7 is lowered, forming member 8 contacts metal sheet 5 and forces it into the corresponding corrugation 3 of the lower die '1. When the upper die 6 is in the lowermost'or closed position, the metal sheet will be shaped to the contour of the Working surfaceof the lower' die member. After the corrugation 4 has been formed in* sheet 5 by formng member 8, the upper die is raised' and the 'sheet 5 is ad- .vanced in the direction of the arrow in Figure 1- to position a second increment of the sheet in alignment with the forming member 8 in preparation for forming a second corrugation. a i

To prevent movement of the metal sheet 5 during the formingprocess, -a pair of spring-biased holding members 9 aredisposed adjacent to the forming member 8 'in the direction of advancement of sheet 5.- 'When the upper die 6 is in its uppermostor open position, the holding members 9 are biased downwardly in relation to die 6 as shown in Figure 1. As the upper die 6 is lowered, the holding members 9 cooperate with the working surface of lower die 1 to clamp the previously formed corrugations disposed therebetween prior to and during the forming process. V e

The upper surface of each of the holding members 9 is provided with a series of spaced recesses 10 and a series of: threaded openings 11' which are disposed alternately with respect to the recesses 10; The lowersurface of die 6 is formed with a series of recesses 12 which register withrecesses 10 of holding' member 9 and with a series of recesses r13 which register with openings 11. v

i To bias the holding members 9 downwa-rdly, sprngs "14 are disposed in the aligned recesses 10 and 12 and serve to urge the members 9-downwardly toward the lower die 1.- i w The holding members 9 are connected to the upper die 6 bya series of studslS. The lower end of studs 15 arethreadedly engaged in openingsll and the upper contact the metal sheet, and as it is lowered further, the springs 14 will become compressed resulting in the holding member 9 being forced into close, intimate contact with the metal corrugations disposed thereunder. The compression of the springs 14 and necessarily the clamping effect of the holding members 9 increases as the upper die 6 reaches its closed position. As the forrning member 8 engages and forms the metal sheet, movement 'o'f the sheet is prevented by the holding members 9.

To prevent the incoming sheet from kickng up during the forming proce'ss,-a clamping bar 13 is disposed adjacent the forming member on the side of the 'forming member opposite that adjoining the holding member. The clamping bar is vertically movable in relation to the 'upper die 6 and for that purpose, a series of longitudinally spaced recesses 19 and a series of alternately spaced threaded openings 26 are disposed in the upper surface of the clamping bar. A like series of register- 'ing recesses 21 and 22 are disposed in the lower surface of the upper die. Springs 23 are disposed in the a-lternate recesses 19 and extend into recesses 21. The openings are each adapted to threadably receive a stud '24 which is provided with a stud head 25. Stud 24 and stud heads 25 extend into the registering recesses 22 which have a flush lock ring 26 to provide a shoulder 27 at the entrance of each recess. The lock ring 26- is rigidly Secured to the upper die 6 by screws or other suitable attachment means, not shown. 'when in contact with shoulder 27, serves to connect the 'clamping bar 18 to upper die 6. A similar clamping bar 28 is rigidly attached to the lower die 1 and is disposed to cooperate with clamping bar 18 to clamp metal sheet 5 therebetween as the upper die 6 moves toward its closed position.

'In operation, the clamping bar 18 is based downwardly *with respect to die 6 when the dies `are in their open position, as shown in Figure 1. The downwardly based position of clamping bar 18, as shown in Figure 1, is a slight distance below the lower tip of forming member 8. As the platen 7 is lowered, the clamping bar 13 initially engages sheet 5 and theholding members bottom in the corresponding corrugations of lower die 1 before the forming 'member 8 engages the sheet 5.

The holding members 9, which bear against the previously formed corrugations 4 through the force of the compressed springs 14, serve to prevent the slippage of the 'sheet during the forming operation, while the clamping bar '18 functions to prevent the incoming portion of the 'sheet from 'kicking upwardly during the forming.

The clamping bar does not prevent slippage of the sheet, "but instead permits slippage or movement of the sheet "during forming so that the sheet can be deformed into the corrugation 3 of lower die 1 without stretching of "the metal. This insures that the metal will have a uni- 'form thickness throughout the region of the corrugations.

The'holding or clamping effect of both the clamping bar and the holding members may be readily increased by varying the number of springs, the length of the 'springs, the overall length of the registering recesses into which the springs are disposed, the material from which "the springs are 'formed and/ or the number of the holding members and clamping bars.

'To insure unformity and accuracy in the corrugations, a plurality of sizing or shaping members 29 are disposed adjacent to the holding members in the direction of advancement of sheet 5. The sizing members 29 are 'for-med integral with upper die 6. As the upper die 6 is moved downwardly and a corrugation 4 is being formed :in the -manner previous ly described, the sizing members 29 engage the metal corrugations 4 disposed thereunder and force them into intimate 'contact with the working surface of the lower die 1. Thus, imperfectly shaped or sized corrugations will be reformed to the eXtent necessary to attain the desired contour. Each corruga- Stud head 25,

'23 and into position under the form'ing member 8.

tion 4 is subjected to a series of these Operations as each sizing member in turn contacts the advancing metal sheet.

As the previously formed portion of sheet 5 may tend to curl or warp upwardly around the end of the outermost sizing member 29'during the forming operation, a straightening member 3@ is Secured to upper die 6 and disposed adjacent to sizing members 253* in the direction of advancement of sheet 5. Member 30 serves merely to contact and restrain corrugations 4 from curlng upward thereby insur'ng that the completed metal sheet will be generally flat.

To prevent curling of the sheet, the peak or ridge 31 of the outermost corrugation of lower die 1 has a con plete radius of curvature. While the straightening member 36 is shown as a full corrugation Secured to die 6, the member need only have a width sufiicient to cooperate with the complete radius of ridge 31.

in operation, when the upper die 6 is in its uppermost or open position, as shown in Figure l, the sheet metal 5 to be corrugated is advanced, either manually or automatically, into the apparatus overclamping bar In this position, the spring 23 and 14 will urge clamping bar 13 and the holding members 9, respectively, to their downward extended position. As the die 6 is lowered, the forming member '8 contacts the metal and forces the metal into the corrugation 3 disposed immediately below member 8 in the working surface of lower die 1 shaping it to the contour of the surface. As previously set forth, the clamping bar 18 engages the sheet prior to engagement of the sheet by forming member 8 and prevents the uncorrugated portion of the sheet from kicking up during forming. In forming the initial corrugation in sheet 5, the 'holding members 9 and sizing members 29 merely register with the corrugations 3 in the working surface of die 1 and perform no useful purpose at this time.

After the first corrugation is fo'rmed, the upper die 6 is raised, and clamping bar 18 and holding members 9 will remain in contact with the metal sheet during the initial upward movement of die 6 due to the action of springs 23. When stud heads 25 and 16 contact the upper edge of shoulders 27 and 17, respectively, the

'clamping bar 18 and holding members 9 move upward With 'die 6 as a single unit. The metal sheet is then advanced forwardly, inthe direction of the arrow in Figure l, far enough to allow the previously formed corrugation to .repose in the succeeding corrugation in the working surface of die 1.

Die 6 is then again lowered. The holding member 9 adjacent to the forming member 8 will engage the previously formedmetal corrugation 4 now disposed thereunder before forming member 8 contacts sheet 5. i

In further lowering of upper die 6, the forming member 8 contacts the metal sheet 5 and, as previously described, the springs 14 'become highly compressed increasng the clamping effect of members 9. Thus, dur

'ing the forming operation, metal sheet 5 is effectivelyse cured against movement.

As succesive corrugations are formed and 'the metal sheet advanced, the metal corrugations 4 of sheet 5 will register wth the sizing members 29. Members 29 serve to coop'erate with the corrugated working surface of die 1 to size the corrugations disposed therebetween as upper die 6 is lowered.

As the metal sheet is advanced and the corrugations 4 of sheet 5 move past the outermost sizing members 29, they successively are contacted by the straightening member 30 and are restrained from curling upwardly as successive corrugations are being formed.

The novel structure of this apparatus, permits a continuous series of accurate, relatively deep corrugations to be formedin a metal sheet. This is accomplished by utilizingsimple,`yettefective` means for holding the metal sheet in place' during the forming process and by subjecting the formed corrugations to a series of shapng Operations as the metal sheet is advanced through the apparatus. Additional refinements consist of means for insuring that the metal sheet remains in a horizontal planecas it is fed into the apppar-atus while, at the same time, preventing movement thereof during the forming process, and means for insuring alignment of the corrugations in the finished metal sheet. Maintenance costs are kept to a minimum by the compact, rugged construction of the apparatus containing relatively few moving parts.

Various modes of carrying out the invention are contemplated as being within the scope of the following claims particularly pointing out and distinctly claiming the subject matter which is regarded as the invention.

Iclaim: p

l. In an apparatus for forming relatively deep corrugations in a metal sheet; a first die member having a Working surface formed of a seriesvof corrugations; and a second die member movable relative to said first die member and comprising a forming member disposed to cooperate with said working surface of the first die mernber to successively form corrugations in the metal sheet, a plurality of holding members movable with respect to said forming member and located forWardly of said forming member along the path of travel of said metal sheet and disposed to clamp the previously formed corrugations to the first die member Working surface to prevent movement of the sheet as successive corrugations are formed, said holding members being normally biased from said forming member towards said first die member to engage said sheet prior to said forming member, and a plurality of sizing members located forwardly of the holding members in the path' of travel of the sheet and disposed to cooperate with the working surface of the first die member to shape and size those corrugations previously disposed between the holding members and first die working surface, said sizing members being fixedly mounted with respect to said forming member and disposed to act in unison therewith.

2. In an apparatus for successively forming a series of relatively deep corrugations in asmetal sheet as said sheet is progressively advanced through the apparatus and having a first die member having a working surface formed of a series of corrugations, a second die member mov able with respect to said first die member and having a working surface complementary to that of the first die member, said second die member being comprised of a forming member disposed to cooperate with said first working surface to successively form corrugatons in the metal sheet, holding means movable with respect to said forrning member and located adjacent to said forming member in the direction of advancement of said sheet and disposed to cooperate with said first die member working surface to clamp the previously formed corrugations therebetween and prevent movement of the sheet as successive corrugations are formed, means for biasing said holding means toward the working surface of said die member to efiect engagement of said holding means with said corrugated metal sheet prior to the forming member engaging said sheet, and sizing means located adjacent said holding means in the direction of advancement of said sheet and disposed to cooperate with said first die member working surface to size the previously formed corrugations, said sizing means being fixedly mounted with respect to said forming member and disposed to act in unison with said forming member.

3. In an apparatus for successively forming a series of relatively deep corrugations in a metal sheet as said sheet is progressively advanced through the apparatus: a first die member having a working surface formed of a series of corrugations; and 'a second die member movable with respect to said first die member and comprising a forming member disposed to cooperate with the working surface of said first die member to successively form corrugations in the metal sheet, holding means movable relative to said forming member and located 'adjacent to said forming member in the direction of advancement of said sheet and disposed to cooperate with the working surface of said first 'die member to clamp the previously formed corrugations therebetween and prevent movement of .the sheet as successive corrugations are formed, means for biasing said holding means from said 'forming member and toward the working surface of said first die member to effect engagement of said holding means with `said corrugated metal sheet prior to the forming member engaging said sheet, sizing means `located adjacent said holding means in *the* direction of advancement of said sheet anddisposed to cooperate with the working surface ofwsaid first die member to size the previously formed corrugations, said sizing means being fixedly mounted with respect to said forming member and disposed to act in unison with said forming member, and means fixedly mounted with respect to said forming member and located adjacent said sizing means in the direction of advancement of the sheet for preventng warping of the portion of the previously formed sheet extending outwardly of the -apparatus during the formation of successive corrugations.

4. In an apparatus for successively forming a series of relatively deep corrugations in a metal sheet as said sheet is incrementally advanced through said -apparatusz a first 'die member having 'a working surface formed of a series of corrugations; and a second die member movable relative to said first die member and comprising a forming member disposed to cooperate with the working surface of said first die member' to successively form corrugations in the metal sheet, a plurality of holding members movable relative to said forming member and located adjacent to said fonning member in the direction of advancemet of the sheet and disposed to cooperate With the working surface of said first die member to clamp the previously formed corrugations therebetween and prevent movement of the sheet as successive corrugations are formed, means for biasing said holding members from said `forming member and toward said working surface of the first die member to elfect engagement of said holding members wit-h said corrugated metal sheet prior to the forming member engaging said sheet, a plurality of sizing members fixedly mounted relative to said forming member and located adjacent to said holding members in the direction of advancement of the sheet and disposed to co-operate with the working surface of said first die member =to size the previously formed corrugations, sheet engaging means movable with respect to said forming member and disposed on the opposite side of the forming member from said holding members and engageable with a corresponding means fixedly mounted on said first die member for slidably clamping the unformed portion of the metal sheet during the formation of corrugations, and means for biasing said sheet engaging means from said forming member and toward said working surface of the first die member to elfect engagement of said sheet engaging means 'with said sheet prior to the forming member engaging said sheet.

5. In an apparatus for successively forming a series of relatively deep corrugations in a metal sheet 'as said sheet is incrementally 'advanced through said appara-tus and having a first die member having a working surface formed of ra series of corrugations, a second die member movable with respect to said first die member and comprising a forming member disposed to cooperate With the 'working surface of saidfirst die member to successively form corrugations in the metal sheet, a plurality of holding members movable relative to said forming member :and located adjacent to said formingmember in the ,7 4 direction of advancement of the sheet and disposed to cooperate with said first die member working surface to clamp the previously formed corrugations therebetween and prevent movement of the sheet as successive corrugations are formed, means for biasing said holding members from said forming member toward the working surface of the first die member to efiect engagement of said holding members With said corrugated metal sheet prior to the formng member engaging said sheet, aplunahty of sizing members fixedly mounted relative to said forming member and located adjacent said holding members in the direction of `advancement of the sheet 'and disposed to co-operate with the Working surface of said first die member to size the previously formed corrugations; clampingmeans movable relative to said forming mem ber and including a bar located on the opposite side of the forming member from said holding members and adapted to engage -a second bar associated with the said first die member to slidingly clamp the unformed portion of the metal sheet therebetween during the formation of corrugatons, means for biasing said first bar from said 8 forming member toward the second bar to effect engagement of said first bar with said 'metal sheet prior to said forming member engaging said sheet, and anti-sheet'cu'ling means fixedly mounted relative to said onming member `and located adj acent to said sizing members for- Wardly of the Working su'fiace of the first die member in the direction of advancement of the sheet for engagng previously formed sheet corrugations upon sheet advancement from the first die member to prevent curling of the sheet during the formng and sizing of successive corrugations.

References Cited in the file of this patent UNITED STATES PATENTS 1,5 11,349 

